Ingenuity Helps Assuage Network Access Cravings

April 2000
By Clarence A. Robinson, Jr.

Nifty software tool automates federal agency spectrum assignment applications, avoids overlap, interference.

Powerful forces of private-sector competition and an onslaught of technical advances are propelling the United States into a telecommunications renaissance era. In every sector—wireless, wireline, local and long distance, video and Internet—more services are being delivered at lower prices and higher bandwidth.

Access, broadband and competition, called the ABCs of telecommunications, are bringing advanced services. However, it takes enormous effort by the government and potential competitors alike to interject rivalry into the commercial marketplace. This is especially the case in the $100 billion U.S. local telephone market, traditionally controlled by monopoly franchises. Technology advances and the Telecommunications Act of 1996 are helping to change this equation.

The warp speed of telecommunications advances requires a traffic cop to avoid conflicts, interference and bottlenecks. This is the U.S. government’s role, involving the careful application of technology along with innovative assignment and use of the electromagnetic spectrum. In a white-hot marketplace, the private sector is seeking access to exclusive government spectrum, either by reallocation or increased sharing.

In the United States, responsibility for domestic spectrum management is shared by two organizations. The Federal Communications Commission (FCC) is responsible for nongovernment spectrum allocation and control. The National Telecommunications and Information Administration (NTIA) handles government agency spectrum management.

A branch of the Commerce Department, the NTIA relies on its Office of Spectrum Management (OSM) in Washington, D.C., and its research and engineering arm, the Institute for Telecommunication Sciences (ITS) in Boulder, Colorado, to carry out its key tasks in government allocation and use of the spectrum. Heading the NTIA is Gregory L. Rohde, assistant secretary of commerce for communications and information. His organization advises the president and secretary of commerce on domestic and international communications and information issues.

The NTIA also negotiates U.S. agreements for spectrum allocation with other countries through the International Telecommunications Union (ITU) and a recurring World Radio Conference.

Sharing the electromagnetic spectrum to accommodate the advent of new technologies is complicated, especially when many parts of the spectrum already are allocated for multiple services. In the U.S. market, the issue is not only conflicting government and private sector use but also persistent frequency-sharing issues within the government’s own spectrum allocation, William T. Hatch maintains. He is the OSM’s acting administrator.

On the domestic front, the OSM is searching for new and improved methods to manage spectrum in the face of intricate new technologies emerging at a breakneck pace, he explains. Spectrum sharing requires careful planning to avoid interference such as when high-power radar systems are adjacent to fixed satellite-service bands, where out-of-band emissions can cause severe interference problems.

Constant coordination with the FCC is necessary, especially for commercial sector spectrum auctions, Hatch declares. A new automation tool, however, is available for use by both the NTIA and the FCC. This tool helps speed decisions on commercial licenses and federal agency spectrum assignments, Fred R. Wentland, OSM director of plans and policies, notes.

The tool automates the request for frequency assignment and reviews radio communications systems planned for the future—important functions when 300 to 500 assignment actions are processed each day by the OSM, Wentland claims. The paperwork for requests can be overwhelming, and the NTIA must carefully examine each application to make certain that it complies with the rules and regulations and avoids spectrum interference. Each application must be checked against some 6,000 federal agencies with spectrum assignments in the OSM’s master file.

The automation tool alleviates the paperwork burden, allowing federal employees to generate spectrum allocation applications that are forwarded electronically to the NTIA, Wentland illustrates. Each applicant also can check electronically to see that the submission complies with all rules involved. Software in federal agencies’ personal computers enables those filing spectrum applications to analyze data to assure that interference does not exist before submitting their applications.

This joint spectrum management system software provides database information on approximately 400,000 spectrum assignments. With the automated system’s parameters, federal agencies requesting frequency assignments have an immediate idea of interference potential. Information from the FCC spectrum allocations can also be inserted into the system for the agency’s use in private-sector assignments vis-a-vis federal agency assignments, he continues.

More than 200 federal agency managers have attended a week-long training program on the effective use of the joint spectrum management system. Wentland recalls that training classes for this voluntary program are booked for the next nine months.

On the international front, the OSM is the U.S. government’s voice in worldwide spectrum issues. Hatch explains that the organization is spending significant resources to prepare for the World Radio Conference in Istanbul, Turkey, from May 8 to June 2. One of the major issues to be discussed is preservation of space-to-earth spectrum from 1559 megahertz to 1610 megahertz for the NAVSTAR global positioning system (GPS) operating in the L1 band.

The United States has expressed concern over a proposal to use the lower portion of the 1559-megahertz band for mobile satellite communications. This item was delayed until the 2000 conference, but detailed OSM studies clearly show that frequency sharing in this band is not feasible, Hatch points out. Concerned about GPS interference, the U.S. government has already informed the world body of its findings in a preliminary meeting. He anticipates that conference participants will examine other areas of the spectrum for mobile satellite communications use.

A related conference issue involves space-to-space spectrum allocation for GPS satellite cross-links. The space-to-space frequency is expected to be at 1176 megahertz, plus or minus 12 megahertz, in the upper portion of the L5 band. This band is from 960 megahertz to 1215 megahertz, generally for use in aeronautical radio navigation. Many satellites, both commercial and government, use GPS signals for orbital position fixes.

Another conference-related item will be spectrum allocation for third-generation international mobile telecommunications, or 3G IMT 2000. This technology involves spectrum-sharing conditions with nongeostationary, fixed-orbit satellite service.

The conference agenda also includes discussions on the use of satellite earth stations aboard cruise ships, an item that involves both the NTIA and the FCC. New spectrum allocations for passive sensors used in radio astronomy and earth exploration satellites above 70 gigahertz are slated as agenda items as well, Hatch states.

As the central research and engineering laboratory for the government, the ITS brings technical resources to bear for objective assessments of telecommunications technologies and their impact on the spectrum. The laboratory contributes expertise to the executive branch, especially in cutting-edge technology issues, according to Val M. O’Day, acting director of the institute.

An example of ITS research involves smart antenna technology for next-generation cellular telephones and personal communications services (PCS). The institute has developed an advanced antenna testbed to evaluate new designs, improve telecommunications services and reduce costs. This research is also part of the NTIA’s goal to improve spectrum efficiency. Known as smart or adaptive antennas, they can continuously change their radiation pattern to improve system performance.

Mounted at the base station, adaptive antennas are effective in tracking mobile users and can diminish the interference caused by the signal reflecting off buildings and other obstructions. The antennas also increase channel capacity by enabling more calls to share the same bandwidth. Numerous companies are in the process of developing adaptive antenna systems.

The Boulder-based testbed provides a standard platform for making accurate and repeatable measurements of adaptive antenna systems. The key elements are the local neighborhood test cell and a small multichannel (currently eight), high-bandwidth (approximately 10 megahertz) measurement system.

The ITS assists other agencies such as the Federal Aviation Administration (FAA) and the departments of Defense, Agriculture and Transportation, in meeting communications requirements that support their missions, O’Day discloses. The institute also offers commercial communications companies direct technical support, which he considers extremely important work.

The institute’s activity with industry involves cooperative research and development agreements with vendors, O’Day reveals. The laboratory assists companies with various state-of-the-art telecommunications research, and the companies provide their equipment, research staffs and funding in this collaborative effort, he notes.

One of the reasons the institute is located in Colorado is the terrain and demographics of the region. At a high altitude, the facility is also adjacent to a national radio quiet zone. This nontransmission site, established by the FCC and the state, is for radio communications research, O’Day reports. The institute’s operation is highly leveraged, with a budget of approximately $10 million a year and between 60 and 100 federal employees. A significant part of the funding comes from reimbursement by federal agencies and industry.

O’Day believes the institute’s most important function is to provide technical support for the OSM. The laboratory conducts engineering work to assist the NTIA in federal spectrum management responsibilities. The laboratory also cooperates with the FCC whenever joint spectrum use is involved. The facility’s engineering capability harnesses measurement technology to determine spectrum use by federal agencies.

The laboratory generally conducts research in frequencies between 10 kilohertz and 28 gigahertz but is expanding its capability into higher frequencies. This expansion, O’Day assures, is designed to keep pace with technology advances in super high frequency satellite communications, and wideband and ultrawideband technical communications.

The research spans the central frequency ranges not only to ensure federal agency adherence to frequency assignments, the NTIA’s primary function, but also to determine possible interference problems in areas such as land and marine mobile communications. O’Day also points to the institute’s work with the FAA in radar frequencies at selected sites, which he considers extremely important for aviation safety.

A new cost-effective method enables the FAA to measure the performance of the air traffic control radar beacon system antennas in operation at most major airports. The FAA relies on these antennas to locate and identify aircraft without interrupting communications service.

The facility is moving into next-generation wireless technology, including measurement for PCS and for local multipoint distribution services. O’Day adds that scientists are making intrabuilding measurements for microcell technol-ogy as broadband communications move into residential areas. Emphasis within the ITS is to help industry assure the delivery of broadband communications to homes and businesses. Federal agencies also will benefit from broadband applications, he points out.

The laboratory also is assessing technology and helping assure interoperability between public safety wireless and wireline communications. A lack of public safety tactical communications interoperability exists, especially among various law enforcement organizations, O’Day insists. Specifications are being developed so that law enforcement and emergency medical services, as examples, will be able to communicate, he discloses.

An additional area of responsibility for the ITS is development of performance objectives. Here, it is spearheading research that involves advanced audio and video quality. There are far-reaching implications from this research for new Internet applications and for the next-generation Internet, or Internet 2, O’Day claims. This research is resulting in signal standards for both the American National Standards Institute and the ITU. The ITS, along with major universities, is working with industry on Internet 2 and on applications of real-time and interactive video technologies, which he is convinced will emerge for routine use within the next 10 years.

However, the centerpiece of the telecommunications revolution is broadband technology. A type of data transmission, broadband enables a single medium, such as wire, to simultaneously carry a number of channels operating at uniform efficiency. This technology provides high-speed access to the Internet over a wide band of frequencies via cable modems, cable set-top boxes, interactive television, and packet-switched telephony. Broadband speeds are much higher than the 56- or 64-kilobit-per-second modem and are often faster than a 1.5-megabit-per-second T1 line.

Already, broadband technology is spreading. Today, more than 1.7 million customers connect to the Internet at speeds at least 25 times faster than the standard modem. The next step is investment in a broadband infrastructure that will make the Internet faster and usher in the broadband Internet age. In addition, the Internet is migrating from the personal computer into handheld devices such as Palm Pilots, into cars and even into home appliances, FCC Chairman William E. Kennard predicts.

To help stimulate competition, government regulation of the more advanced services is being withheld, assuring availability to all competitors. This approach helps make possible broadband communications delivery to the home over the same line the local telephone company uses to deliver basic service. This digital subscriber line (DSL) technology is available to a growing number of residential areas from numerous providers.

The FCC took action affecting common carriers last November to accelerate the availability of advanced telecommunications services for residential and small business consumers. The commission’s ruling permits competitive carriers to obtain access to the high frequency portion of an incumbent local exchange carriers’ loop over which voice services are provided. This action enables carriers to provide DSL-based services over the same telephone lines simultaneously with basic telephone service, a technique referred to as line sharing.

Line sharing permits the consumer to obtain innovative data services without the need to buy a second line and without having to forego voice service. Incumbent local exchange carriers already are using line-sharing technology to offer basic telephone service and DSL service over the same line. The commission’s action places competitive carriers on an equal footing with incumbent local carriers, while not affecting the incumbent’s ability to offer its own DSL and voice service.

A whole new industry is being created—companies that compete against the traditional local telephone company. There is an alphabet soup of these new carriers, called CAPs (competitive access providers), CLECs (competitive local exchange carriers) and DLECs (digital local exchange carriers). In the past year, the number of new competitive local telephone companies operating their own networks doubled from about 150 to 300, and these companies are adding approximately a million lines every three months, Kennard explains.

Another example of a technical advance is known as third-wire overbuild, or bundling technology. In this approach, services such as local and long-distance telephone, cable television and Internet access are provided in a bundle by a single company, making the price competitive when compared to buying separate services from several providers. A broadband optical fiber platform comes to within 900 feet of a home, providing high-speed voice, video and Internet communications access in densely populated areas. Market penetration is underway along the East and West coasts, where 40 percent of the U.S. population lives.

Clearly, demand for Internet access is transforming the U.S. telecommunications industry and reshaping the national economy. Today, 80 million people use the Internet in the United States, almost a 200 percent increase from 27 million in 1996, and U.S. Internet traffic is doubling every 100 days. More than 40 percent of U.S. households have Internet access, and it is estimated that by 2006, almost half of the U.S. work force will be employed by industries that are either major producers or intensive users of information technology products and services.

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